If you are thinking of buying a Sidekick on E bay read this first !!
The only fully functioning Sidekick that will work in the UK are those originally sold in the UK. They also require a data service subscription to T mobile to use E Mail and Internet. They will not work on any other network for E Mail and Internet.
I bought a Sidekick 2 myself from a dishonest E bay seller under the impression it was from the UK . The reason I bought it was because I wanted E mail and Internet on the move. The seller neglected to inform me the phone was German and that it therefore wouldn't be possible to use this phone in the UK for this. I know this because I checked with T mobile and they confirmed this. ANYONE that tells you a Sidekick bought abroad will work with data services in the UK(E mail and Internet) is not telling the truth, you can confirm this by phoning T mobile yourself. Extensive internet research has confirmed this, If you know a way to get them to work then you haven't shared your secret on the internet yet.
The reason they only work in the country where they are bought is that the users data is backed up on a server in that country. This is why the contents of Paris Hiltons address book were made public last year, she never lost the phone, people hacked in to the server in the US. Each phone only works with the servers of that country.Any Sidekick you buy from the US or Germany to use for browsing the Internet or using E mail would require a T mobile account in those countries and while you were in the UK you would be charged roaming fees and the bills would be astronomical.
BUT If you have a non UK Sidekick bought abroad or off E bay you can use them as a normal phone and you will be able to text. You will still therefore still have a functioning example of the trendiest phone in the world. You will notice that few people selling Sidekicks on E bay mention where the phone is from, presumably this is because of the reasons mentioned above, even if they have a picture of the phone and they tell you it is a UK phone the only way to tell that the phone was bought in the UK is to see it with the box ,instructions and receipt written in English and a photo of it connected to the T Mobile UK network.